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	<div id="winchm_template_title">FIELD_INFO</div>
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	<div id="winchm_template_content"><div id="mainSection"><p>The <b>FIELD_INFO</b> structure is used by the <a href="#Bookmark1076"><b>IG_DUMP_SYMBOL_INFO</b></a><a href="#Bookmark1075"><b>Ioctl</b></a> operation to provide information about a member in a structure.</p>
<h2>Syntax</h2>
<div class="code"><span codelanguage="ManagedCPlusPlus"><table>
<tr>
<th>C++</th>
</tr>
<tr>
<td>
<pre>typedef struct _FIELD_INFO {
  PUCHAR           fName;
  PUCHAR           printName;
  ULONG            size;
  ULONG            fOptions;
  ULONG64          address;
  union {
    PVOID fieldCallBack;
    PVOID pBuffer;
  };
  ULONG            TypeId;
  ULONG            FieldOffset;
  ULONG            BufferSize;
  struct _BitField {
    USHORT Position;
    USHORT Size;
  } BitField;
  ULONG            fPointer  :2;
  ULONG            fArray  :1;
  ULONG            fStruct  :1;
  ULONG            fConstant  :1;
  ULONG            Reserved  :27;
} FIELD_INFO, *PFIELD_INFO;</pre>
</td>
</tr>
</table></span></div>
<h2>Members</h2>
<dl>
<dt><b>fName</b></dt>
<dd>
<p>Specifies the name of the symbol's member to which this structure applies.  Submembers can be specified using the delimiters "<b>.</b>" and "<b>-&gt;</b>".  Unless DBG_DUMP_FIELD_FULL_NAME is set in <b>fOptions</b>, <b>fName</b> is considered to be the beginning of the member name.</p>
</dd>
<dt><b>printName</b></dt>
<dd>
<p>Specifies an alternative name to use when printing the name of the member.  If <b>printName</b> is <b>NULL</b>, the actual name of the member is used when printing the name of the member.</p>
</dd>
<dt><b>size</b></dt>
<dd>
<p>Receives the size in the target's memory, in bytes, of the member that is specified by <b>fName</b>.</p>
<p>If the member is an array, <b>size</b> specifies the number of elements in the array.</p>
</dd>
<dt><b>fOptions</b></dt>
<dd>
<p>Specifies the flags that determine the behavior of the IG_DUMP_SYMBOL_INFO <b>Ioctl</b> operation.  For a description of these flags, see <a href="#Bookmark1079"><b>DBG_DUMP_FIELD_XXX</b></a>.</p>
</dd>
<dt><b>address</b></dt>
<dd>
<p>Receives the address in the target's memory of the member that is specified by <b>fName</b>.  If no address is supplied for the symbol type in SYM_DUMP_PARAM.<b>addr</b>, <b>address</b> receives the offset of the member relative to the beginning of an instance of the type.  For more information about SYM_DUMP_PARAM, see <a href="#Bookmark1076"><b>IG_DUMP_SYMBOL_INFO</b></a>.</p>
</dd>
<dt><b>fieldCallBack</b></dt>
<dd>
<p>Specifies a <a href="#Bookmark1080"><b>PSYM_DUMP_FIELD_CALLBACK</b></a> callback function to be called with the information about the member that is specified by <b>fName</b>.  The callback function is passed a structure with the field information and the value of SYM_DUMP_PARAM.<b>context</b>.</p>
<p>No callback function is called if DBG_DUMP_FIELD_NO_CALLBACK_REQ is set in <b>fOptions</b>, <b>fieldCallBack</b> is <b>NULL</b>, or the <b>Options</b> member of the SYM_DUMP_PARAM structure passed to <b>Ioctl</b> does not have DBG_DUMP_CALL_FOR_EACH set.  If DBG_DUMP_FIELD_COPY_FIELD_DATA is set in <b>fOptions</b>, <b>fieldCallBack</b> is not used.</p>
</dd>
<dt><b>pBuffer</b></dt>
<dd>
<p>Specifies a buffer to receive the value of the member specified by <b>fName</b>.  This member is only used if DBG_DUMP_FIELD_COPY_FIELD_DATA is set in <b>fOptions</b>.</p>
</dd>
<dt><b>TypeId</b></dt>
<dd>
<p>Receives the identifier for the type of the member that is specified by <b>fName</b>.</p>
</dd>
<dt><b>FieldOffset</b></dt>
<dd>
<p>Receives the offset of the member within the structure.</p>
</dd>
<dt><b>BufferSize</b></dt>
<dd>
<p>Specifies the size, in bytes, of the <b>pBuffer</b> buffer.</p>
</dd>
<dt><b>BitField</b></dt>
<dd>
<p>Receives information about bit fields in a structure.
      
	 </p>
<dl>
<dt><b>Position</b></dt>
<dd>
<p>Receives the start position of the bit field.  This is the number of bits from to the beginning of the structure to the bit field.</p>
</dd>
<dt><b>Size</b></dt>
<dd>
<p>Receives the size, in bits, of the bit field.</p>
</dd>
</dl>
</dd>
<dt><b>fPointer</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the member is a pointer.  <b>fPointer</b> is <b>FALSE</b> if the member is not a pointer.  It is 1 if the member is a 32-bit pointer and 3 if the member is a 64-bit pointer.</p>
</dd>
<dt><b>fArray</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the member is an array.  <b>fArray</b> is <b>FALSE</b> if the field is not an array and <b>TRUE</b> if it is.</p>
</dd>
<dt><b>fStruct</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the member is a structure.  <b>fStruct</b> is <b>FALSE</b> if the member is not a structure and <b>TRUE</b> if it is.</p>
</dd>
<dt><b>fConstant</b></dt>
<dd>
<p>Receives a Boolean value that indicates whether the member is a constant.  <b>fConstant</b> is <b>FALSE</b> if the member is not a constant and <b>TRUE</b> if it is.</p>
</dd>
<dt><b>Reserved</b></dt>
<dd></dd>
</dl>
<h2>Remarks</h2>
<p>When calling the <a href="#Bookmark1076"><b>IG_DUMP_SYMBOL_INFO</b></a><a href="#Bookmark1075"><b>Ioctl</b></a> operation, the <b>fName</b> member of this structure should be set to the name of the symbol's member to which this structure applies and the <b>fOptions</b> member should reflect the desired functionality of the operation.  The other members are either optional, or are filled in by <b>Ioctl</b>.</p>
<h2>Requirements</h2>
<table>
<tr>
<th width="30%">
<p>Header</p>
</th>
<td width="70%">
<dl>
<dt>WdbgExts.h</dt>
</dl>
</td>
</tr>
</table>
<h2><a id="see_also"></a>See also</h2>
<dl>
<dt><a href="#Bookmark1076"><b>IG_DUMP_SYMBOL_INFO</b></a></dt>
<dt><a href="#Bookmark1075"><b>Ioctl</b></a></dt>
<dt><a href="#Bookmark1079"><b>DBG_DUMP_FIELD_XXX</b></a></dt>
<dt><a href="#Bookmark1080"><b>PSYM_DUMP_FIELD_CALLBACK</b></a></dt></dl></div></div>	
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